Seido Innocell 1750 Extended Life Battery

Battery life on the HTC Evo 4G isn't the greatest, particularly with 4G use, but thanks to its user-replaceable battery, you can always carry a spare and swap out cells when you're low on juice and away from an outlet. If you're on the road a lot or are a power user, the $50 Seido Innocell 1750 Extended Life Battery is a must-have.